It is usually difficult to break the ceramic surface over a glass cooktop, but it could happen if a heavy pan or another object falls on it. If your ceramic glass cooktop has a crack or chip on its surface, there is no need to worry. Gather all of the materials you need to do the repair and then get to work.
Dampen a cloth with denatured alcohol and rub it over the cooktop surface to remove grease and other buildup. Dry the surface with another dry cloth and let it air-dry for a few minutes.
Rub the damaged area gently with the fine-grit sandpaper. This will help remove loose ceramic shards and also roughen the surface, making it easier for the compound to bond with it.
Combine the filler paste and hardener in the container, using the spatula. The ratio should be 20 parts filler and one part hardener.
Smooth the compound into the crack with the popsicle stick. Use the paintbrush to help direct the compound into other fine cracks and chipped areas. Allow it to dry for 24 hours, and then use the fine-grit sandpaper again to smooth it out.
Clean the repair with a small amount of denatured alcohol on a soft cloth.